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Unprecedented frequency of mitochondrial introns in colonial bilaterians. Sci Rep 2022; 12:10889. [PMID: 35764672 PMCID: PMC9240083 DOI: 10.1038/s41598-022-14477-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 06/07/2022] [Indexed: 11/16/2022] Open
Abstract
Animal mitogenomes are typically devoid of introns. Here, we report the largest number of mitochondrial introns ever recorded from bilaterian animals. Mitochondrial introns were identified for the first time from the phylum Bryozoa. They were found in four species from three families (Order Cheilostomatida). A total of eight introns were found in the complete mitogenome of Exechonella vieirai, and five, 17 and 18 introns were found in the partial mitogenomes of Parantropora penelope, Discoporella cookae and Cupuladria biporosa, respectively. Intron-encoded protein domains reverse transcriptase and intron maturase (RVT-IM) were identified in all species. Introns in E. vieirai and P. penelope had conserved Group II intron ribozyme domains V and VI. Conserved domains were lacking from introns in D. cookae and C. biporosa, preventing their further categorization. Putative origins of metazoan introns were explored in a phylogenetic context, using an up-to-date alignment of mitochondrial RVT-IM domains. Results confirmed previous findings of multiple origins of annelid, placozoan and sponge RVT-IM domains and provided evidence for common intron donor sources across metazoan phyla. Our results corroborate growing evidence that some metazoans with regenerative abilities (i.e. placozoans, sponges, annelids and bryozoans) are susceptible to intron integration, most likely via horizontal gene transfer.
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Kovalčíková J, Vrbacký M, Pecina P, Tauchmannová K, Nůsková H, Kaplanová V, Brázdová A, Alán L, Eliáš J, Čunátová K, Kořínek V, Sedlacek R, Mráček T, Houštěk J. TMEM70 facilitates biogenesis of mammalian ATP synthase by promoting subunit c incorporation into the rotor structure of the enzyme. FASEB J 2019; 33:14103-14117. [DOI: 10.1096/fj.201900685rr] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Jana Kovalčíková
- Department of Bioenergetics, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Marek Vrbacký
- Department of Bioenergetics, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Petr Pecina
- Department of Bioenergetics, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Kateřina Tauchmannová
- Department of Bioenergetics, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Hana Nůsková
- Department of Bioenergetics, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Vilma Kaplanová
- Department of Bioenergetics, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Andrea Brázdová
- Department of Bioenergetics, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Lukáš Alán
- Department of Bioenergetics, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Jan Eliáš
- Department of Bioenergetics, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Kristýna Čunátová
- Department of Bioenergetics, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Vladimír Kořínek
- Laboratory of Cell and Developmental Biology, Institute of Molecular Genetics, The Czech Academy of Sciences, Prague, Czech Republic
| | - Radislav Sedlacek
- Institute of Molecular Genetics, The Czech Academy of Sciences, Prague, Czech Republic
- Laboratory of Transgenic Models of Diseases and Czech Centre for Phenogenomics, The Czech Academy of Sciences, Prague, Czech Republic
| | - Tomáš Mráček
- Department of Bioenergetics, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
| | - Josef Houštěk
- Department of Bioenergetics, Institute of Physiology, The Czech Academy of Sciences, Prague, Czech Republic
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Ayyub SA, Varshney U. Translation initiation in mammalian mitochondria- a prokaryotic perspective. RNA Biol 2019; 17:165-175. [PMID: 31696767 DOI: 10.1080/15476286.2019.1690099] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
ATP is generated in mitochondria of eukaryotic cells by oxidative phosphorylation (OXPHOS). The OXPHOS complex, which is crucial for cellular metabolism, comprises of both nuclear and mitochondrially encoded subunits. Also, the occurrence of several pathologies because of mutations in the mitochondrial translation apparatus indicates the importance of mitochondrial translation and its regulation. The mitochondrial translation apparatus is similar to its prokaryotic counterpart due to a common origin of evolution. However, mitochondrial translation has diverged from prokaryotic translation in many ways by reductive evolution. In this review, we focus on mammalian mitochondrial translation initiation, a highly regulated step of translation, and present a comparison with prokaryotic translation.
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Affiliation(s)
- Shreya Ahana Ayyub
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
| | - Umesh Varshney
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India.,Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
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4
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Alternative Splicing of the Delta-Opioid Receptor Gene Suggests Existence of New Functional Isoforms. Mol Neurobiol 2018; 56:2855-2869. [PMID: 30066306 DOI: 10.1007/s12035-018-1253-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 07/17/2018] [Indexed: 12/26/2022]
Abstract
The delta-opioid receptor (DOPr) participates in mediating the effects of opioid analgesics. However, no selective agonists have entered clinical care despite potential to ameliorate many neurological and psychiatric disorders. In an effort to address the drug development challenges, the functional contribution of receptor isoforms created by alternative splicing of the three-exonic coding gene, OPRD1, has been overlooked. We report that the gene is transcriptionally more diverse than previously demonstrated, producing novel protein isoforms in humans and mice. We provide support for the functional relevance of splice variants through context-dependent expression profiling (tissues, disease model) and conservation of the transcriptional landscape in closely related vertebrates. The conserved alternative transcriptional events have two distinct patterns. First, cassette exon inclusions between exons 1 and 2 interrupt the reading frame, producing truncated receptor fragments comprising only the first transmembrane (TM) domain, despite the lack of exact exon orthologues between distant species. Second, a novel promoter and transcriptional start site upstream of exon 2 produces a transcript of an N-terminally truncated 6TM isoform. However, a fundamental difference in the exonic landscaping as well as translation and translation products poses limits for modelling the human DOPr receptor system in mice.
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Pecina P, Nůsková H, Karbanová V, Kaplanová V, Mráček T, Houštěk J. Role of the mitochondrial ATP synthase central stalk subunits γ and δ in the activity and assembly of the mammalian enzyme. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:374-381. [DOI: 10.1016/j.bbabio.2018.02.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 02/05/2018] [Accepted: 02/24/2018] [Indexed: 10/17/2022]
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6
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Vrbacký M, Kovalčíková J, Chawengsaksophak K, Beck IM, Mráček T, Nůsková H, Sedmera D, Papoušek F, Kolář F, Sobol M, Hozák P, Sedlacek R, Houštěk J. Knockout of Tmem70 alters biogenesis of ATP synthase and leads to embryonal lethality in mice. Hum Mol Genet 2018; 25:4674-4685. [PMID: 28173120 DOI: 10.1093/hmg/ddw295] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/22/2016] [Accepted: 08/23/2016] [Indexed: 12/24/2022] Open
Abstract
TMEM70, a 21-kDa protein localized in the inner mitochondrial membrane, has been shown to facilitate the biogenesis of mammalian F1Fo ATP synthase. Mutations of the TMEM70 gene represent the most frequent cause of isolated ATP synthase deficiency resulting in a severe mitochondrial disease presenting as neonatal encephalo-cardiomyopathy (OMIM 604273). To better understand the biological role of this factor, we generated Tmem70-deficient mice and found that the homozygous Tmem70-/- knockouts exhibited profound growth retardation and embryonic lethality at ∼9.5 days post coitum. Blue-Native electrophoresis demonstrated an isolated deficiency in fully assembled ATP synthase in the Tmem70-/- embryos (80% decrease) and a marked accumulation of F1 complexes indicative of impairment in ATP synthase biogenesis that was stalled at the early stage, following the formation of F1 oligomer. Consequently, a decrease in ADP-stimulated State 3 respiration, respiratory control ratio and ATP/ADP ratios, indicated compromised mitochondrial ATP production. Tmem70-/- embryos exhibited delayed development of the cardiovascular system and a disturbed heart mitochondrial ultrastructure, with concentric or irregular cristae structures. Tmem70+/- heterozygous mice were fully viable and displayed normal postnatal growth and development of the mitochondrial oxidative phosphorylation system. Nevertheless, they presented with mild deterioration of heart function. Our results demonstrated that Tmem70 knockout in the mouse results in embryonic lethality due to the lack of ATP synthase and impairment of mitochondrial energy provision. This is analogous to TMEM70 dysfunction in humans and verifies the crucial role of this factor in the biosynthesis and assembly of mammalian ATP synthase.
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Affiliation(s)
- Marek Vrbacký
- Department of Bioenergetics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jana Kovalčíková
- Department of Bioenergetics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic.,First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Kallayanee Chawengsaksophak
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic.,Laboratory of Transgenic Models of Diseases, Division BIOCEV, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Inken M Beck
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Tomáš Mráček
- Department of Bioenergetics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Hana Nůsková
- Department of Bioenergetics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - David Sedmera
- Department of Cardiovascular Morphogenesis, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic,Institute of Anatomy, First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - František Papoušek
- Department of Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - František Kolář
- Department of Developmental Cardiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Margarita Sobol
- Laboratory of Biology of the Cell Nucleus, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Pavel Hozák
- Laboratory of Biology of the Cell Nucleus, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Radislav Sedlacek
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic.,Laboratory of Transgenic Models of Diseases, Division BIOCEV, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Josef Houštěk
- Department of Bioenergetics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
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Sulo P, Szabóová D, Bielik P, Poláková S, Šoltys K, Jatzová K, Szemes T. The evolutionary history of Saccharomyces species inferred from completed mitochondrial genomes and revision in the 'yeast mitochondrial genetic code'. DNA Res 2017; 24:571-583. [PMID: 28992063 PMCID: PMC5726470 DOI: 10.1093/dnares/dsx026] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 05/23/2017] [Indexed: 11/24/2022] Open
Abstract
The yeast Saccharomyces are widely used to test ecological and evolutionary hypotheses. A large number of nuclear genomic DNA sequences are available, but mitochondrial genomic data are insufficient. We completed mitochondrial DNA (mtDNA) sequencing from Illumina MiSeq reads for all Saccharomyces species. All are circularly mapped molecules decreasing in size with phylogenetic distance from Saccharomyces cerevisiae but with similar gene content including regulatory and selfish elements like origins of replication, introns, free-standing open reading frames or GC clusters. Their most profound feature is species-specific alteration in gene order. The genetic code slightly differs from well-established yeast mitochondrial code as GUG is used rarely as the translation start and CGA and CGC code for arginine. The multilocus phylogeny, inferred from mtDNA, does not correlate with the trees derived from nuclear genes. mtDNA data demonstrate that Saccharomyces cariocanus should be assigned as a separate species and Saccharomyces bayanus CBS 380T should not be considered as a distinct species due to mtDNA nearly identical to Saccharomyces uvarum mtDNA. Apparently, comparison of mtDNAs should not be neglected in genomic studies as it is an important tool to understand the origin and evolutionary history of some yeast species.
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Affiliation(s)
- Pavol Sulo
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Bratislava 842 15, Slovakia
| | - Dana Szabóová
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Bratislava 842 15, Slovakia
| | - Peter Bielik
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Bratislava 842 15, Slovakia
| | - Silvia Poláková
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Bratislava 842 15, Slovakia
| | - Katarína Šoltys
- Comenius University Science Park, Bratislava 841 04, Slovakia
| | - Katarína Jatzová
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University, Bratislava 842 15, Slovakia
| | - Tomáš Szemes
- Comenius University Science Park, Bratislava 841 04, Slovakia
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University, Bratislava 842 15, Slovakia
- Geneton s.r.o., Galvaniho 7, Bratislava 821 04, Slovakia
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Ayyub SA, S L A, Dobriyal D, Aluri S, Spremulli LL, Varshney U. Fidelity of translation in the presence of mammalian mitochondrial initiation factor 3. Mitochondrion 2017; 39:1-8. [PMID: 28804013 DOI: 10.1016/j.mito.2017.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 06/14/2017] [Accepted: 08/07/2017] [Indexed: 11/29/2022]
Abstract
Initiation factor 3 (IF3) is a conserved translation factor. Mutations in mitochondrial IF3 (IF3mt) have been implicated in disease pathology. Escherichia coli infCΔ55, compromised for IF3 activity, has provided an excellent heterologous system for IF3mt structure-function analysis. IF3mt allowed promiscuous initiation from AUA, AUU and ACG codons but avoided initiation with initiator tRNAs lacking the conserved 3GC pairs in their anticodon stems. Expression of IF3mt N-terminal domain, or IF3mt devoid of its typical N-, and C-terminal extensions improved fidelity of initiation in E. coli. The observations suggest that the IF3mt terminal extensions relax the fidelity of translational initiation in mitochondria.
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Affiliation(s)
- Shreya Ahana Ayyub
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Aswathy S L
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Divya Dobriyal
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Srinivas Aluri
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
| | - Linda L Spremulli
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3290, USA
| | - Umesh Varshney
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India; Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064, India.
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Tavares WC, Seuánez HN. Disease-associated mitochondrial mutations and the evolution of primate mitogenomes. PLoS One 2017; 12:e0177403. [PMID: 28510580 PMCID: PMC5433710 DOI: 10.1371/journal.pone.0177403] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 04/26/2017] [Indexed: 01/09/2023] Open
Abstract
Several human diseases have been associated with mutations in mitochondrial genes comprising a set of confirmed and reported mutations according to the MITOMAP database. An analysis of complete mitogenomes across 139 primate species showed that most confirmed disease-associated mutations occurred in aligned codon positions and gene regions under strong purifying selection resulting in a strong evolutionary conservation. Only two confirmed variants (7.1%), coding for the same amino acids accounting for severe human diseases, were identified without apparent pathogenicity in non-human primates, like the closely related Bornean orangutan. Conversely, reported disease-associated mutations were not especially concentrated in conserved codon positions, and a large fraction of them occurred in highly variable ones. Additionally, 88 (45.8%) of reported mutations showed similar variants in several non-human primates and some of them have been present in extinct species of the genus Homo. Considering that recurrent mutations leading to persistent variants throughout the evolutionary diversification of primates are less likely to be severely damaging to fitness, we suggest that these 88 mutations are less likely to be pathogenic. Conversely, 69 (35.9%) of reported disease-associated mutations occurred in extremely conserved aligned codon positions which makes them more likely to damage the primate mitochondrial physiology.
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Affiliation(s)
- William Corrêa Tavares
- Programa de Genética, Instituto Nacional de Câncer, Rio de Janeiro, Rio de Janeiro, Brazil
- Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Departamento de Zoologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Héctor N. Seuánez
- Programa de Genética, Instituto Nacional de Câncer, Rio de Janeiro, Rio de Janeiro, Brazil
- Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
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Alila-Fersi O, Chamkha I, Majdoub I, Gargouri L, Mkaouar-Rebai E, Tabebi M, Tlili A, Keskes L, Mahfoudh A, Fakhfakh F. Co segregation of the m.1555A>G mutation in the MT-RNR1 gene and mutations in MT-ATP6 gene in a family with dilated mitochondrial cardiomyopathy and hearing loss: A whole mitochondrial genome screening. Biochem Biophys Res Commun 2017; 484:71-78. [DOI: 10.1016/j.bbrc.2017.01.070] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 01/15/2017] [Indexed: 01/11/2023]
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11
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Felhi R, Mkaouar-Rebai E, Sfaihi-Ben Mansour L, Alila-Fersi O, Tabebi M, Ben Rhouma B, Ammar M, Keskes L, Hachicha M, Fakhfakh F. Mutational analysis in patients with neuromuscular disorders: Detection of mitochondrial deletion and double mutations in the MT-ATP6 gene. Biochem Biophys Res Commun 2016; 473:61-66. [PMID: 26993169 DOI: 10.1016/j.bbrc.2016.03.050] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 03/13/2016] [Indexed: 12/16/2022]
Abstract
Mitochondrial diseases encompass a wide variety of pathologies characterized by a dysfunction of the mitochondrial respiratory chain resulting in an energy deficiency. The respiratory chain consists of five multi-protein complexes providing coupling between nutrient oxidation and phosphorylation of ADP to ATP. In the present report, we studied mitochondrial genes of complex I, III, IV and V in 2 Tunisian patients with mitochondrial neuromuscular disorders. In the first patient, we detected the m.8392C>T variation (P136S) in the mitochondrial ATPase6 gene and the m.8527A>G transition at the junction MT-ATP6/MT-ATP8 which change the initiation codon AUG to GUG. The presence of these two variations in such an important gene could probably affect the ATP synthesis in the studied patient. In the second patient, we detected several known variations in addition to a mitochondrial deletion in the major arc of the mtDNA eliminating tRNA and respiratory chain protein genes. This deletion could be responsible of an inefficient translation leading to an inefficient mitochondrial protein synthesis in P2.
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Affiliation(s)
- Rahma Felhi
- Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax, Université de Sfax, Tunisia
| | - Emna Mkaouar-Rebai
- Département des Sciences de la Vie, Faculté des Sciences de Sfax, Université de Sfax, Tunisia.
| | | | - Olfa Alila-Fersi
- Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax, Université de Sfax, Tunisia
| | - Mouna Tabebi
- Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax, Université de Sfax, Tunisia
| | - Bochra Ben Rhouma
- Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax, Université de Sfax, Tunisia
| | - Marwa Ammar
- Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax, Université de Sfax, Tunisia
| | - Leila Keskes
- Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax, Université de Sfax, Tunisia
| | | | - Faiza Fakhfakh
- Département des Sciences de la Vie, Faculté des Sciences de Sfax, Université de Sfax, Tunisia
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Banerjee A, Roy S, Behere GT, Roy SS, Dutta SK, Ngachan SV. Identification and characterization of a distinct banana bunchy top virus isolate of Pacific-Indian Oceans group from North-East India. Virus Res 2014; 183:41-9. [PMID: 24468493 DOI: 10.1016/j.virusres.2014.01.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Revised: 01/15/2014] [Accepted: 01/16/2014] [Indexed: 12/23/2022]
Abstract
Banana bunch top virus (BBTV) is considered to be a serious threat to banana production. A new isolate of the virus (BBTV-Umiam) was identified and characterized from local banana mats growing in mid-hills of Meghalaya in North-East India. The complete nucleotide sequence analysis revealed the presence of six full-length ssDNA components (DNA R, DNA U3, DNA S, DNA M, DNA C and DNA N) sharing major common region (CR-M) and a stem-loop common region (CR-SL). BBTV-Umiam showed a unique deletion of 20 nucleotides in the intergenic region of DNA R, the absence of predicted open reading frame (ORF) in DNA U3 and probability for a small ORF in DNA U3 expecting functional evidence at transcriptional level. Phylogenetic analysis based on 88 complete nucleotide sequence of BBTV DNA R available in GenBank generated two broad clusters of Pacific-Indian Oceans (PIO) and South-East Asian (SEA) groups including BBTV-Umiam within PIO cluster. However, BBTV-Umiam was identified as the most distinct member of the PIO group with 100% bootstrap support. This was further supported by the phylogenetic grouping of each genomic component of BBTV-Umiam at the distant end of PIO group during clustering of 21 complete BBTV sequences. BBTV-Umiam shared relatively less nucleotide identity with PIO group for each genomic component (85.0-95.4%) and corresponding ORF (93.8-97.5%) than that of earlier PIO isolates (91.5-99.6% and 96.0-99.3%, respectively). Recombination analysis revealed two intra-component and five inter-component recombination events in BBTV-Umiam, but none of them was unique. Moreover, the isolate was identified as major parental sequence for intra-component recombination event spanning the replication-associated protein encoding region in Tongan BBTV DNA R. The current study indicated differential evolution of BBTV in North-East India (Meghalaya). The natural occurrence of hybrids of Musa balbisiana and M. acuminata in this geographically isolated region could be the contributing factor in accumulating genetic distinctiveness in BBTV-Umiam which need further characterization.
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Affiliation(s)
- Amrita Banerjee
- Division of Crop Improvement, ICAR Research Complex for NEH Region, Umiam 793 013, Meghalaya, India.
| | - Somnath Roy
- National Bureau of Plant Genetic Resources, Regional Station, Umiam 793 013, Meghalaya, India
| | - Ganesh T Behere
- Division of Crop Improvement, ICAR Research Complex for NEH Region, Umiam 793 013, Meghalaya, India
| | - Subhra Saikat Roy
- ICAR Research Complex for NEH Region, Manipur Centre, Lamphelpat 795 004, Manipur, India
| | - Sudip Kumar Dutta
- ICAR Research Complex for NEH Region, Mizoram Centre, Kolasib 796 081, Mizoram, India
| | - S V Ngachan
- Division of Crop Improvement, ICAR Research Complex for NEH Region, Umiam 793 013, Meghalaya, India
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Yu NT, Zhang YL, Feng TC, Wang JH, Kulye M, Yang WJ, Lin ZS, Xiong Z, Liu ZX. Cloning and sequence analysis of two banana bunchy top virus genomes in Hainan. Virus Genes 2012; 44:488-94. [PMID: 22286609 DOI: 10.1007/s11262-012-0718-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Accepted: 01/12/2012] [Indexed: 11/29/2022]
Abstract
The genome of Banana bunchy top virus (BBTV) consists of six segments of single-stranded DNA of approximately 1 kb in length. We identified and sequenced the complete genomes of two BBTV isolates, one with and one without satellite DNA, from Haikou, Hainan, China. The Haikou-2 isolate contains six genomic segments and an additional satellite DNA while the Haikou-4 isolate contains only six genomic segments. Typical of other babuviruses, each genomic segment encodes a single open reading frame and contains the highly conserved stem-loop and major common regions. Phylogenetic analysis of the two Haikou isolates together with existing sequence records in GenBank confirmed the grouping of BBTV into two large groups and further refined the geographical distribution of each group. To accommodate the changes in the BBTV geographical distribution, the two groups are proposed as the Southeast Asian group and the Pacific-Indian Oceans group. Both the Haikou-2 and Haikou-4 isolates belong to the newly proposed Southeast Asian group.
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Affiliation(s)
- Nai-Tong Yu
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China
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Adaptation of respiratory chain biogenesis to cytochrome c oxidase deficiency caused by SURF1 gene mutations. Biochim Biophys Acta Mol Basis Dis 2012; 1822:1114-24. [PMID: 22465034 DOI: 10.1016/j.bbadis.2012.03.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Revised: 03/09/2012] [Accepted: 03/12/2012] [Indexed: 01/26/2023]
Abstract
The loss of Surf1 protein leads to a severe COX deficiency manifested as a fatal neurodegenerative disorder, the Leigh syndrome (LS(COX)). Surf1 appears to be involved in the early step of COX assembly but its function remains unknown. The aim of the study was to find out how SURF1 gene mutations influence expression of OXPHOS and other pro-mitochondrial genes and to further characterize the altered COX assembly. Analysis of fibroblast cell lines from 9 patients with SURF1 mutations revealed a 70% decrease of the COX complex content to be associated with 32-54% upregulation of respiratory chain complexes I, III and V and accumulation of Cox5a subunit. Whole genome expression profiling showed a general decrease of transcriptional activity in LS(COX) cells and indicated that the adaptive changes in OXPHOS complexes are due to a posttranscriptional compensatory mechanism. Electrophoretic and WB analysis showed that in mitochondria of LS(COX) cells compared to controls, the assembled COX is present entirely in a supercomplex form, as I-III₂-IV supercomplex but not as larger supercomplexes. The lack of COX also caused an accumulation of I-III₂ supercomplex. The accumulated Cox5a was mainly present as a free subunit. We have found out that the major COX assembly subcomplexes accumulated due to SURF1 mutations range in size between approximately 85-140kDa. In addition to the originally proposed S2 intermediate they might also represent Cox1-containing complexes lacking other COX subunits. Unlike the assembled COX, subcomplexes are unable to associate with complexes I and III.
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15
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Vanderperre B, Staskevicius AB, Tremblay G, McCoy M, O'Neill MA, Cashman NR, Roucou X. An overlapping reading frame in the PRNP gene encodes a novel polypeptide distinct from the prion protein. FASEB J 2011; 25:2373-86. [PMID: 21478263 DOI: 10.1096/fj.10-173815] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The prion protein gene PRNP directs the synthesis of one of the most intensively studied mammalian proteins, the prion protein (PrP). Yet the physiological function of PrP has remained elusive and has created controversies in the literature. We found a downstream alternative translation initiation AUG codon surrounded by an optimal Kozak sequence in the +3 reading frame of PRNP. The corresponding alternative open reading frame encodes a polypeptide termed alternative prion protein (AltPrP) with a completely different amino acid sequence from PrP. We introduced a hemagglutinin (HA) tag in frame with AltPrP in PrP cDNAs from different species to test the expression of this novel polypeptide using anti-HA antibodies. AltPrP is constitutively coexpressed with human, bovine, sheep, and deer PrP. AltPrP is localized at the mitochondria and is up-regulated by endoplasmic reticulum stress and proteasomal inhibition. Generation of anti-AltPrP antibodies allowed us to test for endogenous expression of AltPrP in wild-type human cells expressing PrP. By transfecting cells with siRNA against PrP mRNA, we repressed expression of both PrP and AltPrP, confirming endogenous expression of AltPrP from PRNP. AltPrP was also detected in human brain homogenate, primary neurons, and peripheral blood mononuclear cells. These results demonstrate an unexpected function for PRNP, which, in addition to plasma membrane-anchored PrP, also encodes a second polypeptide termed AltPrP.
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Affiliation(s)
- Benoît Vanderperre
- Department of Biochemistry, Faculty of Medicine, University of Sherbrooke, 3001 12ème Avenue Nord, Sherbrooke, QC, J1H 5N4, Canada
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16
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Mayr JA, Havlícková V, Zimmermann F, Magler I, Kaplanová V, Jesina P, Pecinová A, Nusková H, Koch J, Sperl W, Houstek J. Mitochondrial ATP synthase deficiency due to a mutation in the ATP5E gene for the F1 epsilon subunit. Hum Mol Genet 2010; 19:3430-9. [PMID: 20566710 DOI: 10.1093/hmg/ddq254] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023] Open
Abstract
F1Fo-ATP synthase is a key enzyme of mitochondrial energy provision producing most of cellular ATP. So far, mitochondrial diseases caused by isolated disorders of the ATP synthase have been shown to result from mutations in mtDNA genes for the subunits ATP6 and ATP8 or in nuclear genes encoding the biogenesis factors TMEM70 and ATPAF2. Here, we describe a patient with a homozygous p.Tyr12Cys mutation in the epsilon subunit encoded by the nuclear gene ATP5E. The 22-year-old woman presented with neonatal onset, lactic acidosis, 3-methylglutaconic aciduria, mild mental retardation and developed peripheral neuropathy. Patient fibroblasts showed 60-70% decrease in both oligomycin-sensitive ATPase activity and mitochondrial ATP synthesis. The mitochondrial content of the ATP synthase complex was equally reduced, but its size was normal and it contained the mutated epsilon subunit. A similar reduction was found in all investigated F1 and Fo subunits with the exception of Fo subunit c, which was found to accumulate in a detergent-insoluble form. This is the first case of a mitochondrial disease due to a mutation in a nuclear encoded structural subunit of the ATP synthase. Our results indicate an essential role of the epsilon subunit in the biosynthesis and assembly of the F1 part of the ATP synthase. Furthermore, the epsilon subunit seems to be involved in the incorporation of subunit c to the rotor structure of the mammalian enzyme.
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Affiliation(s)
- Johannes A Mayr
- Department of Pediatrics, Paracelsus Medical University, Salzburg A5020, Austria
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17
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Havlícková V, Kaplanová V, Nůsková H, Drahota Z, Houstek J. Knockdown of F1 epsilon subunit decreases mitochondrial content of ATP synthase and leads to accumulation of subunit c. BIOCHIMICA ET BIOPHYSICA ACTA 2010; 1797:1124-9. [PMID: 20026007 DOI: 10.1016/j.bbabio.2009.12.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Revised: 12/11/2009] [Accepted: 12/13/2009] [Indexed: 10/20/2022]
Abstract
The subunit epsilon of mitochondrial ATP synthase is the only F1 subunit without a homolog in bacteria and chloroplasts and represents the least characterized F1 subunit of the mammalian enzyme. Silencing of the ATP5E gene in HEK293 cells resulted in downregulation of the activity and content of the mitochondrial ATP synthase complex and of ADP-stimulated respiration to approximately 40% of the control. The decreased content of the epsilon subunit was paralleled by a decrease in the F1 subunits alpha and beta and in the Fo subunits a and d while the content of the subunit c was not affected. The subunit c was present in the full-size ATP synthase complex and in subcomplexes of 200-400 kDa that neither contained the F1 subunits, nor the Fo subunits. The results indicate that the epsilon subunit is essential for the assembly of F1 and plays an important role in the incorporation of the hydrophobic subunit c into the F1-c oligomer rotor of the mitochondrial ATP synthase complex.
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Affiliation(s)
- Vendula Havlícková
- Department of Bioenergetics, Institute of Physiology and Centre for Applied Genomics, Academy of Sciences of the Czech Republic, 142 20 Prague
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18
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Muhlia-Almazan A, Martinez-Cruz O, Navarrete del Toro MDLA, Garcia-Carreño F, Arreola R, Sotelo-Mundo R, Yepiz-Plascencia G. Nuclear and mitochondrial subunits from the white shrimp Litopenaeus vannamei F(0)F(1) ATP-synthase complex: cDNA sequence, molecular modeling, and mRNA quantification of atp9 and atp6. J Bioenerg Biomembr 2008; 40:359-69. [PMID: 18770013 DOI: 10.1007/s10863-008-9162-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Accepted: 05/16/2008] [Indexed: 01/29/2023]
Abstract
We studied for the first time the ATP-synthase complex from shrimp as a model to understand the basis of crustacean bioenergetics since they are exposed to endogenous processes as molting that demand high amount of energy. We analyzed the cDNA sequence of two subunits of the Fo sector from mitochondrial ATP-synthase in the white shrimp Litopenaeus vannamei. The nucleus encoded atp9 subunit presents a 773 bp sequence, containing a signal peptide sequence only observed in crustaceans, and the mitochondrial encoded atp6 subunit presents a sequence of 675 bp, and exhibits high identity with homologous sequences from invertebrate species. ATP9 and ATP6 protein structural models interaction suggest specific functional characteristics from both proteins in the mitochondrial enzyme. Differences in the steady-state mRNA levels of atp9 and atp6 from five different tissues correlate with tissue function. Moreover, significant changes in the mRNA levels of both subunits at different molt stages were detected. We discussed some insights about the enzyme structure and the regulation mechanisms from both ATP-synthase subunits related to the energy requirements of shrimp.
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Affiliation(s)
- Adriana Muhlia-Almazan
- Molecular Biology Lab, Centro de Investigación en Alimentación y Desarrollo (CIAD), A. C., Sonora, Mexico.
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19
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Abstract
Permeant cationic fluorescent probes are widely employed to monitor mitochondrial transmembrane potential and its changes. The application of such potential-dependent probes in conjunction with both fluorescence microscopy and fluorescence spectroscopy allows the monitoring of mitochondrial membrane potential in individual living cells as well as in large population of cells. These approaches to the analysis of membrane potential is of extremely high value to obtain insights into both the basic energy metabolism and its dysfunction in pathologic cells. However, the use of fluorescent molecules to probe biological phenomena must follow the awareness of some principles of fluorescence emission, quenching, and quantum yield since it is a very sensitive tool, but because of this extremely high sensitivity it is also strongly affected by the environment. In addition, the instruments used to monitor fluorescence and its changes in biological systems have also to be employed with cautions due to technical limits that may affect the signals. We have therefore undertaken to review the most currently used analytical methods, providing a summary of practical tips that should precede data acquisition and subsequent analysis. Furthermore, we discuss the application and feasibility of various techniques and discuss their respective strength and weakness.
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Affiliation(s)
- Giancarlo Solaini
- Dipartimento di Biochimica, Università di Bologna, Via Irnerio 48, Bologna, 40126, Italy.
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20
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Lévêque M, Marlin S, Jonard L, Procaccio V, Reynier P, Amati-Bonneau P, Baulande S, Pierron D, Lacombe D, Duriez F, Francannet C, Mom T, Journel H, Catros H, Drouin-Garraud V, Obstoy MF, Dollfus H, Eliot MM, Faivre L, Duvillard C, Couderc R, Garabedian EN, Petit C, Feldmann D, Denoyelle F. Whole mitochondrial genome screening in maternally inherited non-syndromic hearing impairment using a microarray resequencing mitochondrial DNA chip. Eur J Hum Genet 2007; 15:1145-55. [PMID: 17637808 DOI: 10.1038/sj.ejhg.5201891] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Mitochondrial DNA (mtDNA) mutations have been implicated in non-syndromic hearing loss either as primary or as predisposing factors. As only a part of the mitochondrial genome is usually explored in deafness, its prevalence is probably under-estimated. Among 1350 families with non-syndromic sensorineural hearing loss collected through a French collaborative network, we selected 29 large families with a clear maternal lineage and screened them for known mtDNA mutations in 12S rRNA, tRNASer(UCN) and tRNALeu(UUR) genes. When no mutation could be identified, a whole mitochondrial genome screening was performed, using a microarray resequencing chip: the MitoChip version 2.0 developed by Affymetrix Inc. Known mtDNA mutations was found in nine of the 29 families, which are described in the article: five with A1555G, two with the T7511C, one with 7472insC and one with A3243G mutation. In the remaining 20 families, the resequencing Mitochip detected 258 mitochondrial homoplasmic variants and 107 potentially heteroplasmic variants. Controls were made by direct sequencing on selected fragments and showed a high sensibility of the MitoChip but a low specificity, especially for heteroplasmic variations. An original analysis on the basis of species conservation, frequency and phylogenetic investigation was performed to select the more probably pathogenic variants. The entire genome analysis allowed us to identify five additional families with a putatively pathogenic mitochondrial variant: T669C, C1537T, G8078A, G12236A and G15077A. These results indicate that the new MitoChip platform is a rapid and valuable tool for identification of new mtDNA mutations in deafness.
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Bhargava K, Spremulli LL. Role of the N- and C-terminal extensions on the activity of mammalian mitochondrial translational initiation factor 3. Nucleic Acids Res 2005; 33:7011-8. [PMID: 16340009 PMCID: PMC1310894 DOI: 10.1093/nar/gki1007] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Mammalian mitochondrial translational initiation factor 3 (IF3mt) promotes initiation complex formation on mitochondrial 55S ribosomes in the presence of IF2mt, fMet-tRNA and poly(A,U,G). The mature form of IF3mt is predicted to be 247 residues. Alignment of IF3mt with bacterial IF3 indicates that it has a central region with 20–30% identity to the bacterial factors. Both the N- and C-termini of IF3mt have extensions of ∼30 residues compared with bacterial IF3. To examine the role of the extensions on IF3mt, deletion constructs were prepared in which the N-terminal extension, the C-terminal extension or both extensions were deleted. These truncated derivatives were slightly more active in promoting initiation complex formation than the mature form of IF3mt. Mitochondrial 28S subunits have the ability to bind fMet-tRNA in the absence of mRNA. IF3mt promotes the dissociation of the fMet-tRNA bound in the absence of mRNA. This activity of IF3mt requires the C-terminal extension of this factor. Mitochondrial 28S subunits also bind mRNA independently of fMet-tRNA or added initiation factors. IF3mt has no effect on the formation of these complexes and cannot dissociate them once formed. These observations have lead to a new model for the function of IF3mt in mitochondrial translational initiation.
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Affiliation(s)
| | - Linda L. Spremulli
- To whom correspondence should be addressed. Tel: +1 919 966 1567; Fax: +1 919 966 3675;
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22
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Plásek J, Vojtísková A, Houstek J. Flow-cytometric monitoring of mitochondrial depolarisation: from fluorescence intensities to millivolts. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2005; 78:99-108. [PMID: 15664496 DOI: 10.1016/j.jphotobiol.2004.09.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2004] [Revised: 09/23/2004] [Accepted: 09/24/2004] [Indexed: 11/16/2022]
Abstract
Redistribution potentiometric dyes represent a powerful tool for monitoring membrane potential of mitochondria, especially when these dyes are used with flow cytometry. In particular, tetramethylrhodamine methyl ester proved to be suitable for the screening of mitochondrial membrane potential in cultured human skin fibroblasts from patients suffering from different defects of oxidative phosphorylation. We have developed a method that makes it possible to measure the changes in mitochondrial membrane potential, or to assess the differences between respective mitochondrial membrane potentials in investigated cells and controls in the absolute scale of millivolts. Our approach employs the fact that a logarithmic transformation of Nernst equation-controlled intensity of fluorescence from potentiometric dyes accumulated in mitochondria leads to a linear scale for mitochondrial membrane potentials.
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Affiliation(s)
- J Plásek
- Faculty of Mathematics and Physics, Institute of Physics, Charles University, Ke Karlovu 5, 121 16 Prague, Czech Republic.
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23
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Ješina P, Tesařová M, Fornůsková D, Vojtíšková A, Pecina P, Kaplanová V, Hansíková H, Zeman J, Houštěk J. Diminished synthesis of subunit a (ATP6) and altered function of ATP synthase and cytochrome c oxidase due to the mtDNA 2 bp microdeletion of TA at positions 9205 and 9206. Biochem J 2005; 383:561-71. [PMID: 15265003 PMCID: PMC1133750 DOI: 10.1042/bj20040407] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Dysfunction of mitochondrial ATPase (F1F(o)-ATP synthase) due to missense mutations in ATP6 [mtDNA (mitochondrial DNA)-encoded subunit a] is a frequent cause of severe mitochondrial encephalomyopathies. We have investigated a rare mtDNA mutation, i.e. a 2 bp deletion of TA at positions 9205 and 9206 (9205DeltaTA), which affects the STOP codon of the ATP6 gene and the cleavage site between the RNAs for ATP6 and COX3 (cytochrome c oxidase 3). The mutation was present at increasing load in a three-generation family (in blood: 16%/82%/>98%). In the affected boy with severe encephalopathy, a homoplasmic mutation was present in blood, fibroblasts and muscle. The fibroblasts from the patient showed normal aurovertin-sensitive ATPase hydrolytic activity, a 70% decrease in ATP synthesis and an 85% decrease in COX activity. ADP-stimulated respiration and the ADP-induced decrease in the mitochondrial membrane potential at state 4 were decreased by 50%. The content of subunit a was decreased 10-fold compared with other ATPase subunits, and [35S]-methionine labelling showed a 9-fold decrease in subunit a biosynthesis. The content of COX subunits 1, 4 and 6c was decreased by 30-60%. Northern Blot and quantitative real-time reverse transcription-PCR analysis further demonstrated that the primary ATP6--COX3 transcript is cleaved to the ATP6 and COX3 mRNAs 2-3-fold less efficiently. Structural studies by Blue-Native and two-dimensional electrophoresis revealed an altered pattern of COX assembly and instability of the ATPase complex, which dissociated into subcomplexes. The results indicate that the 9205DeltaTA mutation prevents the synthesis of ATPase subunit a, and causes the formation of incomplete ATPase complexes that are capable of ATP hydrolysis but not ATP synthesis. The mutation also affects the biogenesis of COX, which is present in a decreased amount in cells from affected individuals.
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Affiliation(s)
- Pavel Ješina
- *Department of Bioenergetics, Institute of Physiology and Centre for Integrated Genomics, Academy of Sciences of the Czech Republic, Vídeňská 1083, 142 20 Prague, Czech Republic
| | - Markéta Tesařová
- †Department of Pediatrics and Institute for Inherited Metabolic Disorders, 1st Faculty of Medicine, Charles University, 120 00 Prague, Czech Republic
| | - Daniela Fornůsková
- †Department of Pediatrics and Institute for Inherited Metabolic Disorders, 1st Faculty of Medicine, Charles University, 120 00 Prague, Czech Republic
| | - Alena Vojtíšková
- *Department of Bioenergetics, Institute of Physiology and Centre for Integrated Genomics, Academy of Sciences of the Czech Republic, Vídeňská 1083, 142 20 Prague, Czech Republic
| | - Petr Pecina
- *Department of Bioenergetics, Institute of Physiology and Centre for Integrated Genomics, Academy of Sciences of the Czech Republic, Vídeňská 1083, 142 20 Prague, Czech Republic
| | - Vilma Kaplanová
- *Department of Bioenergetics, Institute of Physiology and Centre for Integrated Genomics, Academy of Sciences of the Czech Republic, Vídeňská 1083, 142 20 Prague, Czech Republic
| | - Hana Hansíková
- †Department of Pediatrics and Institute for Inherited Metabolic Disorders, 1st Faculty of Medicine, Charles University, 120 00 Prague, Czech Republic
| | - Jiří Zeman
- †Department of Pediatrics and Institute for Inherited Metabolic Disorders, 1st Faculty of Medicine, Charles University, 120 00 Prague, Czech Republic
| | - Josef Houštěk
- *Department of Bioenergetics, Institute of Physiology and Centre for Integrated Genomics, Academy of Sciences of the Czech Republic, Vídeňská 1083, 142 20 Prague, Czech Republic
- To whom correspondence should be addressed (email )
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24
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Szczepanowska J, Zabłocki K, Duszyński J. Influence of a mitochondrial genetic defect on capacitative calcium entry and mitochondrial organization in the osteosarcoma cells. FEBS Lett 2005; 578:316-22. [PMID: 15589839 DOI: 10.1016/j.febslet.2004.11.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2004] [Revised: 11/03/2004] [Accepted: 11/09/2004] [Indexed: 10/26/2022]
Abstract
Effects of T8993G mutation in mitochondrial DNA (mtDNA), associated with neurogenical muscle weakness, ataxia and retinitis pigmentosa (NARP), on the cytoskeleton, mitochondrial network and calcium homeostasis in human osteosarcoma cells were investigated. In 98% NARP and rho(0) (lacking mtDNA) cells, the organization of the mitochondrial network and actin cytoskeleton was disturbed. Capacitative calcium entry (CCE) was practically independent of mitochondrial energy status in osteosarcoma cell lines. The significantly slower Ca(2+) influx rates observed in 98% NARP and rho(0), in comparison to parental cells, indicates that proper actin cytoskeletal organization is important for CCE in these cells.
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Affiliation(s)
- Joanna Szczepanowska
- Department of Cellular Biochemistry, Nencki Institute of Experimental Biology, Pasteura 3, 02 093 Warsaw, Poland.
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25
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Kong QP, Yao YG, Sun C, Zhu CL, Zhong L, Wang CY, Cai WW, Xu XM, Xu AL, Zhang YP. Phylogeographic analysis of mitochondrial DNA haplogroup F2 in China reveals T12338C in the initiation codon of the ND5 gene not to be pathogenic. J Hum Genet 2004; 49:414-423. [PMID: 15278763 DOI: 10.1007/s10038-004-0170-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2004] [Accepted: 05/06/2004] [Indexed: 11/29/2022]
Abstract
In this report, we studied on a homoplasmic T12338C change in mitochondrial DNA (mtDNA), which substituted methionine in the translational initiation codon of the NADH dehydrogenase subunit 5 gene ( ND5) with threonine. This nucleotide change was originally identified in two mtDNAs belonging to haplogroup F2 by our previous complete sequencing of 48 mtDNAs. Since then, a total of 76 F2 mtDNAs have been identified by the variations occurring in the hypervariable segments and coding regions among more than 3,000 individuals across China. As the T12338C change was detected in 32 samples representing various sub-clades of the F2 haplogroup while not in 14 non-F2 controls, we believe that the T12338C change is specific to the F2 haplogroup. As F2 and its sub-clades were widely distributed in normal individuals of various Chinese populations, we conclude that T12338C is not pathogenic. In addition, based on the average distribution frequency, haplotype diversity and nucleotide diversity of haplogroup F2 in the populations across China, the T12338C nucleotide substitution seems to have been occurred in north China about 42,000 years ago. Our results provided a good paradigm for distinguishing a polymorphic change from a pathogenic mutation based on mtDNA phylogeny.
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Affiliation(s)
- Qing-Peng Kong
- Laboratory of Cellular and Molecular Evolution, and Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, China
- Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming, 650091, China
- Graduate School of the Chinese Academy of Sciences, Beijing, 100039, China
| | - Yong-Gang Yao
- Laboratory of Cellular and Molecular Evolution, and Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, China
- The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Chang Sun
- Laboratory of Cellular and Molecular Evolution, and Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, China
- Graduate School of the Chinese Academy of Sciences, Beijing, 100039, China
| | - Chun-Ling Zhu
- Laboratory of Cellular and Molecular Evolution, and Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, China
| | - Li Zhong
- Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming, 650091, China
| | - Cheng-Ye Wang
- Laboratory of Cellular and Molecular Evolution, and Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, China
- Graduate School of the Chinese Academy of Sciences, Beijing, 100039, China
| | - Wang-Wei Cai
- Department of Biochemistry, Hainan Medical College, Haikou, 571101, China
| | - Xiang-Min Xu
- Department of Medical Genetics, First Military Medical University, Guangzhou, 510515, China
| | - An-Long Xu
- College of Life Sciences, Zhongshan University, Guangzhou, 510275, China
| | - Ya-Ping Zhang
- Laboratory of Cellular and Molecular Evolution, and Molecular Biology of Domestic Animals, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650223, China.
- Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming, 650091, China.
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Houstek J, Mrácek T, Vojtísková A, Zeman J. Mitochondrial diseases and ATPase defects of nuclear origin. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2004; 1658:115-21. [PMID: 15282182 DOI: 10.1016/j.bbabio.2004.04.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2004] [Revised: 04/01/2004] [Accepted: 04/20/2004] [Indexed: 10/26/2022]
Abstract
Dysfunctions of the F(1)F(o)-ATPase complex cause severe mitochondrial diseases affecting primarily the paediatric population. While in the maternally inherited ATPase defects due to mtDNA mutations in the ATP6 gene the enzyme is structurally and functionally modified, in ATPase defects of nuclear origin mitochondria contain a decreased amount of otherwise normal enzyme. In this case biosynthesis of ATPase is down-regulated due to a block at the early stage of enzyme assembly-formation of the F(1) catalytic part. The pathogenetic mechanism implicates dysfunction of Atp12 or other F(1)-specific assembly factors. For cellular energetics, however, the negative consequences may be quite similar irrespective of whether the ATPase dysfunction is of mitochondrial or nuclear origin.
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Affiliation(s)
- Josef Houstek
- Institute of Physiology and Centre for Integrated Genomics, Academy of Sciences of the Czech Republic, Vídenská 1083, CZ 142 20 Prague 4-Krc, Czech Republic.
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